Blackman was born in London and raised in Leatherhead in Surrey by her parents, Hilda, a sculptor and author, and Richard Seligman, a chemical engineer.
[2] After attending Wimbledon High School in London, Blackman spent two years, from 1924, at a Kunstgewerbeschule in Graz in Austria before returning to England to study at Goldsmiths College School of Art until 1930 and then at the University of Reading from 1931 until 1935.
[6][5] Later in her life she produced more abstract pieces, including paintings in both watercolour and gouache.
[2] Blackman was a regular exhibitor with the Society of Women Artists, SWA, and at the Royal Academy in London.
[5] Living in Boar's Hill near Oxford, she married Geoffrey Blackman, the Sibthorpian professor of rural economy at Oxford University, and she was long associated with that University's St Cross College, where several examples of her sculpture and pottery are held and a room is named in her memory.